Jean jacques heilmann



(No Madel.)

J. J. HEILMANN. ELECTRIC LOOOMOTION ONRAILWAYS.

No. 527,244. Patented Oct. 9, 1894.

* UNITED STATES PATENT OFFICE JEAN JAoo U ns HEILMANN, or PARIS, FRANCE.

ELECTRIC LOCQMOTION ON RAILWAYS.

SPECIFICATION forming part of Letters Patent No. 527,244, dated October 9, 1894.

PP filed Ap l 20, 1894- Serial No. 508.297- (No model.) Patented in France February 22, 1894,1510. 286,493; in Belgium February 24, 1894, No. 108,723, and in England March 12, 1894,}10. 5,118.

To all whom it may concern:

Be it known that I, JEAN JACQUES HEIL- MANN, a citizen of the French Republic, residing at Paris, in the Department of the Seine, France, have invented certain new and useful Improvements in Electrolocomotion on Railways, (patented in Great Britain March 12, 1894, No. 5,118; in France February 22, 1894, No. 236,493, and in Belgium February 24, 1894, No. 108,723,) of which the following is a specification.

This invention relates to that system of electric locomotion for railways described in and by the specification of British Letters Patent granted to me, No. 11,653, dated July 25, A. D. 1890, according to which electro-motors driving some or all of the axles of the train derive their current from a generating dynamo or dynamos carried by the train itself and driven by a suitable prime motor. These improvements are equally applicable where the electro-motors drive only the axles of the locomotive, and to the more general case where they are employed to drive some or all of the axles of the train. In each case the arrangement is practically the same.

When a steam engine is employed in this system of electro-locomotion to drive the dynamo, it is called upon to furnish a very variable amount of power, according to the grade of the road and the state of the rails upon which the train is running. At present, the means employed for controlling the variable amount of work consist in varying the admission of steam or in throttling it; but both these means for known reasons are defective, and it is desirable to have a fixed cutofi, since the efiiciency of any particular engine is always at its maximum with one particular degree of expansion, and diminishes with either a greater or less degree. When engines moreover having dead centers are employed to drive the generators difticulty is sometimes experienced in starting from dead centers.

The object of this invention then is to permit the engine to work with a constant cutoff and consequently always under the most favorable conditions, or in other words so that the work done is always proportional to the speed of the engine, irrespective of the speed of the electro-locomotive and its train,

A further object is to enable the driving engine to be started when it has stopped upon a dead center.

For the purpose of this invention the generating dynamo'is arranged to be variably excited by means of a special exciting dynamo driven by a separate engine. The variable excitation may be controlled by means of a rheostat intercalated in the field magnet circuit. If the excitation be diminished, the intensity of the magnetic field is also diminished and the intensity in the armature increases until the torque has again acquired its previous value. In consequence the speed of the engine has automatically increased, owing to the sole fact of the diminution of excitation, the Work of the engine being augmented while the cut-oft remains the same.

The contrary result happens if the excitation be increased.

For the purpose of starting the engine from a dead center the generating dynamo may be temporarily employed as a motor at the moment of starting, deriving its current from the exciting dynamo, which is driven, as hereinbefore described bya separate engine.

The steam engine gives a constant couple, inasmuch as the admission remains constant, but the couple in the dynamo is proportional to the product of the field-magnet by the intensity in the armature. It is therefore necessary when the intensity in the armature increases, as for example when ascending an incline, that the field should be reduced so that the couple may remain constant. To in crease the power, then, the excitation of the principal dynamo must be reduced. For this purpose, a rheostat is intercalated in the inductor circuit and this circuit is supplied by a special dynamo of constant potential.

The appended diagrams will enable this invention to be more readily understood.

In the diagrams, Figure 1 represents the scheme of connections, and Fig. 2 the arrange ment of the apparatus.

G is the generating dynamo and E its ex citing machine. The current from the ex citer passes through the rheostat R and the ammeter a on its way to the generator field magnet coils.

r is the regulating rheostat of the exciting I I**- are switches in the separate motor circuits.

0 is a commutator which is arranged to reverse the electro-motors by inverting the connections of the motor magnet coils Z'Z with regard to their armatures R-R When the generating dynamo is employed as a motor to start its driving engine D from a dead center, the exciting machine being driven by its separate engine D, the current from the exciter is passed temporarily into the generator armature by means of the switch I.

In Fig. 2, b b are the terminals of the field circuit of the generating dynamo, and B B the terminals of its armature circuits.

Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that what I claim is- 1. In an electro locomotive system of the type set forth, the combination with a main dynamo driven by an engine having a fixed cut-01f, of an exciting dynamo driven by a separate engine, and a rheostat for varying the current supplied by said exciter to the main field magnets.

2. In an electro locomotive system of the type set forth, the combination with a main dynamo driven at varying speed by an engine having a fixed cut-off, of an exciting dynamo of constant potential, driven by a separate engine, and a rheostat for varying the current supplied by said exciter, substantially as described.

3. In an electro locomotive system of the type set forth, the combination with a main dynamo driven at varying speed by an engine having a fixed cut-off, of an exciting dynamo of constant potential driven by a separate engine, and means for reducing the current supplied by the exciter when the work of the main dynamo is increased, substantially as described.

4. In an electro locomotive system of the type set forth, the combination with a main dynamo driven by a principal engine, of an exciting dynamo driven by a separate engine, circuit connections between said exciter and the armature of the main dynamo, and a switch controlling said connections, whereby the current of the exciter may be passed through the armature of the main dynamo as well as its field, and thus operate it as a motor temporarily, to start the principal engine from a dead center, substantially as described.

In testimony that I claim the foregoing as my invention I have signed my name, in presence of two witnesses, this 6th day of April, A. D. 1894..

JEAN JACQUES IIEILMANN.

Witnesses:

CLYDE SHROPSHIRE, HENRY DANZER. 

